Piston



Dec. 14,1926. 7 v

J. STUNGO I PISTON Jul 16,

Filed m M m N 1 Patented Dec. 14, 19 26.

name s'rA Josnrrr STUNGO, or' ron'rnornj MICHIGAN, Assrenon or ONE-H L TO CHARLES :12? i tenses QarENr serene TALBOT, or DETROIT, MICHIGAN.

PISTON.

, 'Applicationfiled iuly'is, i926; Serial 1%.- 122,798

' This invention relates to the construction v of pistons'for internal combustion engines,

particularly. 'to that type of piston wherein a spiral band of metal extending fora considerable portion ofthe length of thei'piston and constituting a number of circumferential wraps, takes the place of the usual piston rings, and its object is to so construct the piston, and its spiral band-ring that the surtaces'of the spiral-ring may belubricated and prevented from seizing With the outer surface of the piston anduwith the inner surface of the cylinder in which thepiston reciprocates.v

In the acco'mpanyin g, drawing, Figalisan elevation of a pistonembodying the pres Lent invention. "Fig. 2 is ,a section on the line 22 of Fig. 1;

Similarfreterence characters refer to like.

parts inboth'views. ,7

The piston shown in the drawing coinprises abody and a spiral band Wrapped on the body. Tie body l'isgenerally cylindricatwith the usual bosses (notshown) on 1 the inside to receive the piston pin. At its upper end is formedacircumferential flange or'shoulder' 2 While" at the, bottom; is a flange or shoulder 3 formed with a helical" groove usual piston rings. It maybe tormedftrom asleeve of castiron Whichis: slit alongaf spiral line and then sprung open sufficiently.

:to slipjover the: end of the piston bodyi lVhen' the piston is to be inserted in a cylini der,;the spiralban'd mustbe contracted by a properly twisting it; in order that 'its resili 1 ence will cause proper pressure between and the cylinderrwall. I

V I have found that Wl1ena-pis'ton' oft ithis character becomes heated in a cylindenlthat the :closenessof the fit betweenithe' outer 'sur;

face of the spirallband and the cylinder Wall so -interferes with proper lubricationtfthat; both 'the band and the cylinder wall are"in 7 The S11E51 band sake-s ifhe pl ced as surface of the Isleeye. I i

danger of injurya l have also found that when apiston of-thi's character is in operation, the spiralband slides around the body I and thus Wears evenly and Wears-the cylin-' der Wall evenly} In order to facilitate this rotary movement, and to prevent the band seizing on the body of the piston, and to provide proper lubrication for the contact-l1 ing surfaces of the band an'd cylinder, 1. haveflprovided oil holes 6 inthe Wall of the piston body and other holes 7 in thespiral band so that lubricant splashed up into the piston vin the usual manner may flow out through these perforations andcoat the outer surface otthe" piston body. and the inner surface of thespiral band and alsozpene- 'trateto vthe surface of thefcylinder.

The number and position of these perfora-f 'tions in both the piston body andfspiral" band, and the's-izes thereof, Will be detcra mined for each diiterent size of'piston by those skilled inthe art;

'Ic'laim: 1 1; AC. piston for internal combustion en gines comprising hollow substantially ylindrical body having circumferential shoulders space'dapartlongitudinally of the cant,

'bodyyand aspiral' band'of resilient metal mounted on the body betweensaidv shoulders, a: 1

a aid'piston body and said spiral band being perforated to vper'rnit the passage of lubri I d A piston for internal combustion en- 1 'gines comprising a! hollowbody having cir-f curn'ferential shoulders at its ends "and *a 13 spiral metal band mounted on the b'ody tor circumferential movement ibetvreen said .shouldersffand constitutinga resilient sleeve, '7 said body and band being perforated to'perinit thel passageof lubricant from the inte lriorio'f' EllBigbOClY to ,the space :ivithin the sleeve" and 'trom'thatqspace to the; e kiterior 

